fix(ci): use prebuilt cargo-nextest to fix rustc version mismatch

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: haasonsaas

.github/workflows/ci.yml

@@ -77,7 +77,7 @@ jobs:
       - uses: dtolnay/rust-toolchain@1.88.0
       - uses: Swatinem/rust-cache@v2
       - name: Install cargo-nextest
-        run: cargo install cargo-nextest --locked
+        uses: taiki-e/install-action@cargo-nextest
       - name: Test
         run: cargo nextest run